Australia's farmers will need to adapt to cope with a potentially hotter and drier continent as the effects of climate change take hold, scientists say.

As the UN's chief science body meets in Hobart today to update the latest climate modelling, the CSIRO says forecasts show Australia will have to cope with less rainfall, longer dry periods and crops struggling to grow in changing conditions.

"Certainly across most of southern Australia, the projections of the future are for warmer and drier conditions, so when we experience warm and dry conditions, growing those crops, canola, wheat, barley etc will be more challenging in the future," he said.